Surgical depth instrument having neuromonitoring capabilities

ABSTRACT

A device configured to provide a faster and more accurate measurement of depths of holes for placement of bone screws and fastener for bone implant fixation procedures. The device includes a combination of a bone probe for physical examination of a hole drilled in a bone and a depth gauge member for determining a depth of the hole and providing digital measurement of the depth via a display on the instrument and/or via a wireless exchange of measurement data to a remote computing device, such as a tablet or smartphone. The device may further be connected to a separate neuromonitoring device and be used for nerve sensing and/or nerve stimulation by way of the bone probe. For example, the bone probe may include a conductive material such that the distal probe tip acts as an extension of the neuromonitoring device and may be used to sense and/or stimulate nerves.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of, and priority to, U.S.Provisional Application No. 62/417,046, filed Nov. 3, 2016, U.S.Provisional Application No. 62/471,873, filed Mar. 15, 2017, and U.S.Provisional Application No. 62/554,470, filed Sep. 5, 2017, the contentsof each of which are hereby incorporated by reference herein in theirentireties.

FIELD

The present disclosure relates generally to medical devices, and, moreparticularly, to a measuring instrument for use in a bone implantfixation procedure, the measuring instrument including a combination ofa bone probe allowing for physical examination of a hole drilled in abone and a depth gauge member for determining a depth of the hole andproviding a digital measurement of the depth.

BACKGROUND

Orthopedics is a medical specialty concerned with the correction ofdeformities or functional impairments of the skeletal system, especiallythe extremities and the spine, and associated structures, such asmuscles and ligaments. Some orthopedic surgical procedures requiresurgeons to secure a device to one or more bones of a patient. Forexample, in some procedures, the surgeon may span and secure one or morebones, or pieces of a single bone, using a bone plate and one or morefasteners, such as screws. Other bone-related surgical procedures,however, may not require a bone plate and may instead solely rely on theuse of one or more screws (e.g., securing a transplanted tendon).

In such bone-related surgical procedures, before an implant or plate, orsimply the screw itself, can be attached to bone, an opening istypically drilled into the bone to accommodate the screw. With a hole inplace, the surgeon can more easily select a screw of the appropriatelength. However, selecting a screw of appropriate length is critical.For example, if the selected screw is too long, the distal end of thescrew may pass through the end of the drilled hole and cause damage tothe bone and/or protrude entirely through the bone, which can havedeleterious effects, such as damage to surrounding tissue and/or painand discomfort, or more serious complications, for the patient. Forexample, in some instances, the bone may abut against soft tissues thatmay be harmed if the screw is too long and may result in irritation ofor damage to the soft parts. Additionally, a screw that protrudesthrough the bone may be tactilely felt by the patient, may prevent softtissues (e.g., tendons, ligaments, or muscles) from moving over the bonesurface as intended, or may even pierce the skin, which can lead toserious infection and complications.

The selection of an appropriate length screw is particularly importantin spinal fixation procedures, such as lumbar sacral fusion and thecorrection of spinal deformities such as scoliotic curves. As anexample, a screw mounted in the pedicle portion of the human spineshould not extend to a point where the screw contacts the spinal corditself, an event that can cause irreparable nervous system damageincluding paralysis. Accordingly, the determination of a length of thehole is important for choosing the appropriate length screw.

During drilling, the surgeon is typically capable of recognizing theresistance on the drill in order to determine when the drill haspenetrated through the bone. Because the simple act of drilling does notprovide an exact measurement of the depth of the bone itself, a depthgauge is commonly employed for directly measuring the depth of the holefrom the top, drilling side to the bottom, opposite side of the hole.

Currently, many designs are known and utilized for measuring the depthof a hole or bore in a portion of a bone. Generally speaking, thesedesigns utilize a central probe member having a barb at a distal end,and a sleeve or channel member. The probe member is inserted into thepilot hole while the surgeon attempts to find the surface with the barb.More specifically, the probe member is inserted to a depth greater thanthe depth of the pilot hole so that the barb is beyond the oppositeside, at which point the surgeon finds the surface by hooking the barbto the opposite side.

The probe member is received in the sleeve or channel member and mayreciprocate relative thereto. The channel member has graduated markingsalong a portion of its length, typically in inches and/or millimeters. Amarker is laterally secured to the probe member such that, as the probemember shifts relative to the channel member, the marker indicates therelative shift between the probe member and the channel member.Accordingly, once the probe member has been secured to the opposite sideof the bone, the channel member is shifted relative to the probe memberand toward the bone until the channel member abuts the surface of thebone. The depth gauge is then read by examining graduated markingsindicated by the probe member marker.

A number of problems are experienced with this depth gauge. As aninitial point, the components are typically made with surgical-gradestainless steel, and the graduated markings are embossed therein.Therefore, the brightness of the operating room lights on the highlyreflective surface can make the markings difficult to read. The markingsare commonly in small increments, such as millimeters, and surgeonsoften have trouble differentiating between the markings, or notingpartial increments. Reading these gauges, then, often requires carefullyholding the depth gauge as the reading is taken, and a surgeon's effortto closely examine the reading may result in a loss of securement orpurchase of the barb on the bone, thus necessitating a re-measurementand a loss of time.

Furthermore, proper reading of the markings requires a surgeon's eyes tobe properly aligned with the markings. That is, a proper view of themeasurement requires the surgeon to view the gauge from a lateral pointof view so that the view of the probe marker aligned with the graduatedmarkings is proper not distorted by the surgeon's elevated, standingperspective. Therefore, it is often necessary for the surgeon to bendover while using these gauges to view an accurate reading. If the depthgauge is tilted in order to make the reading, the sleeve will shiftrelative to the probe, thus making the measurement inaccurate andpossibly causing the barb to become unsecured, as described above. Inaddition, removal of the depth gauge often causes the measurement to belost. As the bone is essentially clamped, by light pressure, between thedistal end of the channel member and the distal barb of the probemember, it is often necessary to retract the channel member from thebone surface in order to extract the probe from the pilot hole.

SUMMARY

The present disclosure is a medical device for use in a bone implantfixation procedure. The device is configured to provide a faster andmore accurate measure of depth. In particular, the device includes acombination of a bone probe allowing for physical examination of a holedrilled in a bone and a depth gauge member for determining a depth ofthe hole and providing a digital measurement of the depth. Accordingly,the device of the present disclosure is capable of digitally measuringthe depth of an opening in a bone during the same surgical step that asurgeon probes and inspects the interior of the opening.

During a bone-related procedure involving placement of a screw, or otherfastener, it may be desirable to determine whether drilling of the holeresulted in any cracks or openings, either along an interior side wallof the hole or at the base of the hole. Ensuring the integrity of thedrilled hole is important because unintended cracks, openings, orirregularities can increase the risk that the screw will either notsecurely attach itself within the hole or may result in chipping orfragmenting of bone during fastening of the screw within the hole. It isgenerally not possible for a surgeon to visual examine the integrity ofthe drilled hole due to a limited field of view within the hole (drilledholes can be relatively small in width, such as 5 mm or less in someinstances).

The device of the present disclosure includes a bone probe that allowsfor a surgeon to feel the interior side walls and base of the hole tolocate any cracks or other unintended openings or irregularities alongthe interior of the hole. The bone probe generally includes an elongatedshaft slidably mounted within a body of the device serving as a handleadapted for manual manipulation. The elongated shaft of the probeincludes a distal end configured to extend from the body of the deviceduring use. The distal end includes a probing tip for contacting aninterior portion of the hole. At least a portion of the elongated shaftmay be substantially flexible or semi-rigid to provide a proper “feel”to the surgeon during examination of the hole in the bone. For example,the shaft of the bone probe may be substantially non-elastic such thatthe surgeon can apply pressure against the interior wall of the hole tofeel for irregularities or the base of the hole via tactile feedbackprovided by the shaft. In some embodiments, the shaft may be taperedsuch that the shaft narrows in width in a direction towards the probingdistal tip. In this manner, the flexibility of the shaft may increasealong the shaft in a direction toward the probing tip.

The probing tip may include at least a first portion having a shape orcontour that aids the surgeon in detecting surface irregularities (e.g.,cracks, crevices, openings, etc.) on the interior surface of the hole.For example, in some embodiments the first portion may have asubstantially arcuate or curved shape. The arcuate or curved portion mayalso aid the surgeon in locating the bottom or base of the hole so as toallow for the depth of the hole to be measured via the depth gaugemember. The arcuate or curved shape of the first portion of the probingtip may generally lessen risk of tissue irritation that may otherwiseoccur along the interior surface of the hole, which is usually soft andeasily penetrable with less curved and more abrupt surfaces (with sharpor distinct edges). In some embodiments, the first portion may have ageneral spherical shape. In other embodiments, the first portion may besubstantially planar with rounded edges.

The probing tip may also include a second portion positioned oppositethe first portion, wherein the second portion includes an engagementsurface configured to pierce or otherwise establish purchase with aninterior of the hole upon application of sufficient force from thesurgeon. In particular, upon locating the base or bottom of the hole,the surgeon may then apply sufficient force upon the shaft of the boneprobe so that the engagement surface of the probing tip engages andestablishes purchase with a sidewall immediately adjacent the base ofthe hole. Upon establishing engagement, the medical device may bestabilized in position, at which point, the depth gauge member can beused for measuring the depth of the hole. In some embodiments, theengagement surface may include surface texturing to enhance frictionbetween the engagement surface and a portion of bone. For example, insome procedures in which a plate or implants is to be secured withscrews through a bicortical drill hole, the probing tip may extendentirely through the hole (from one side of the bone to the other), atwhich point the surgeon may pull the bone probe back towards the holesuch that the engagement surface of the second portion of the probingtip establishes purchase with one side of the bone, and the surfacetexturing enhances friction between the engagement surface and bone toreduce risk of slippage.

The depth gauge member generally includes a hollow elongated bodyslidably mounted within the body of the device and includes a distal endconfigured to extend from the first end of the body during use. Thehollow elongated body includes a lumen in which at least a portion ofthe bone probe shaft is received within such that the bone probe anddepth gauge member are independently slidable relative to one anotherand the body of the device.

The device further includes at least one sensor configured to generatean electronic signal indicative of a depth of the hole as a result ofsensing a distance between the first end of the device body and thedistal end of the depth gauge member. For example, in one embodiment,upon establishing purchase with a bottom interior surface of the holevia the probing tip, a surgeon need only move the device handle (i.e.,device body) in a direction towards the bone such that the first end ofthe handle contacts a surface of the bone proximate the open end of thehole. The surgeon may then advance the depth gauge member towards hole,such that the distal end of the depth gauge member extends from thefirst end of the device handle and advances into the hole, sliding overthe bone probe. While the bone probe is maintained in engagement withthe bottom of the hole via the probing tip, the depth gauge member maybe advanced in a direction towards the bottom of the hole until thedistal end of the depth gauge member makes contact with the bottom ofthe hole. The bone probe essentially acts as a guide upon which thedepth gauge member slide over when advancing to the bottom of the hole.

The sensor is configured to generate an electronic signal based on adistance between the first end of the body and the distal end of thedepth gauge member, wherein the electronic signal is indicative of atleast a depth of the hole. In particular, the sensor may includeinductive or capacitive elements or assemblies configured to sense thelocation of the distal end of the depth gauge member relative to thefirst end of the device body, and, as a result, generate an electronicsignal representing the distance there between. Accordingly, the senseddistance between the first end of the device handle (when abutting thebone surface) and the distal end of the depth gauge member (whenabutting the bottom of the hole) is the depth of the hole.

It should be noted that the device may include logic or allow foradjustment to the sensing capabilities so as to program the sensor toaccount for other variables when sensing the depth of the hole. Forexample, in some embodiments, certain procedures require fixing a plateor implant to the bone via screws. Accordingly, the screw length mustnot only be sufficient to fill the hole but also long enough to accountfor the thickness of a plate or implant through which it passes whenengaging the hole. Accordingly, in some embodiments, the sensor may beprogrammed so as to account for the thickness of the plate or implantand will further include that thickness in the electronic signalproduced, such that the electronic signal is indicative of the totaldepth that a corresponding screw length will need to cover, includingthe depth of the hole in the bone in addition to the thickness of theplate or implant through which the screw will pass through and the screwhead will engage.

Furthermore, in some instances, first end of the device handle will bedirectly abutting a surface of the plate or implant, which is directlyabutting the surface of the bone, when the surgeon is measuring thedepth. Thus, in this case, the sensor is still able to sense a distancebetween the first end of the device handle and the distal end of thedepth gauge member, which will provide an overall depth, rather thanjust a depth of the hole in the bone.

Accordingly, the digital sensing of the hole depth provides a much moreaccurate measurement than conventional analog depth gauges and alsorequiring very little, if any, input or interpretation from the surgeon.Accordingly, by providing a much more accurate measurement of a holedepth, the surgeon is able to select the correct length screw for anygiven hole so as to improve the chances of a successful surgery.

In some embodiments, the device may further include a display providedon the body and configured to visually provide a digital readout of adepth measurement of the hole based on the electronic signal from thesensor. In other embodiments, the device may be configured to wirelesslycommunicate and exchange data with a separate display or computingdevice, such as, for example, a monitor or panel display, a PC, anotebook, a tablet computer, a smartphone, or other wireless computingdevice.

Upon receiving the electronic signal from the sensor, the separatedisplay or computing device may be configured to visually provide thedepth measurement of the hole based on the electronic signal from thesensor. Furthermore, in some embodiments, the computing device mayinclude a specific software application that may be directed tomaintaining a record of the hole measurements and/or provide aninteractive user interface in which multiple holes can be mapped to aparticular plate or implant and the depth of each hole (including thethickness of the plate or implant) can be included and stored forrecords.

In some embodiments, the device may further include a sensor configuredto sense strain of the bone probe shaft. In particular, the sensor mayinclude a strain gauge or the like configured to determine a strain ofthe bone probe shaft, which may be useful for alerting the surgeon of anamount of resistance that the distal probing tip is encountering duringprobing of the interior of the hole. For example, while a surgeon may beable to “feel” the interior surface and further have a sense of when theprobing tip actually makes contact with the bottom of the hole, thestrain sensor may further generate an electronic signal based on asensed strain of the shaft which may then be used to provide an audibleand/or visual alert to the surgeon indicating that the probing tip is infact positioned at the bottom of the hole. For example, the resistanceencountered when the probing tip engages the bottom of the hole may havea certain strain value (i.e., above a certain threshold) which may bedifferent than a resistance encountered with the sidewalls of the hole(which may have a softer, spongier tissue). Accordingly, the audibleand/or visual alert may confirm to a surgeon whether they are in factpositioned at the bottom of the hole or if too much pressure is beingplaced against the interior surface such that they risk possiblyinadvertently piercing the interior surface.

In some embodiments, the device may further be compatible with othermedical devices so as to provide additional features, in additional boneprobing and depth measurement. For example, in some embodiments, thebone probe shaft may include an electrically conductive material (e.g.,a metal such as stainless steel, nitinol, or aluminum), wherein aportion of the bone probe shaft may be exposed, or otherwise accessible,along a portion of the device handle. In particular, the device handlemay include an aperture, window, or the like, that provides access to aninterior of the handle, particularly providing access to an exposedportion of the bone probe shaft. Thus, in some embodiments, anelectrical current from a separate device may be supplied to the boneprobe shaft via the access region (e.g., slide a working tip of anelectrocautery device into the access region to make contact with boneprobe shaft). As a result of being made from a conductive material, thebone probe shaft may carry the electrical current to the distal probetip, which may then be used to deliver energy to a desired target (e.g.,interior surface of hole of the bone) as a result of the electricalcurrent applied thereto. Similarly, a separate nerve sensing/stimulationdevice may be coupled to the conductive bone probe shaft via the accessregion, such that the distal probe tip essentially acts as an extensionto the nerve sensing/stimulation device and may be used tosense/stimulate nerves within the bone.

Yet still, in another embodiment, the handle may include a port incommunication with a portion of the bone probe shaft. The port mayprovide access from an exterior of the handle to an interior of thehandle and to the bone probe shaft. The port may be configured toreceive and place an input connector of a second medical device, such asa neuromonitoring device, for nerve sensing and/or nerve stimulation,into electrical communication with the bone probe shaft, such that thebone probe shaft can be used to carry electrical signals to and from theinput connector of the second medical device.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the claimed subject matter will be apparentfrom the following detailed description of embodiments consistenttherewith, which description should be considered with reference to theaccompanying drawings, wherein:

FIG. 1 is top view of one embodiment of a medical device consistent withthe present disclosure;

FIG. 2 is a cross-sectional view of the medical device of FIG. 1illustrating the hollow interior of the handle and arrangement of thebone probe and depth gauge member relative to one another;

FIGS. 3A and 3B are enlarged front and side views, respectively, of oneembodiment of a probing tip defined on the distal end of the bone probeshaft;

FIGS. 3C and 3D are enlarged front and side views, respectively, ofanother embodiment of a probing tip defined on the distal end of thebone probe shaft;

FIGS. 4A and 4B illustrate retraction of the bone probe within thehandle member and subsequent compression of a spring assembly uponmovement of the handle towards the bone when the probing tip of thedistal end of the bone probe shaft is in contact with the bottom of thedrilled hole in the bone;

FIG. 5 is a side view of the medical device of FIG. 1 including a strainsensor sensing strain upon the bone probe shaft and providing anelectronic signal indicative of the strain to an audio or visualcomponent for providing an audible or visual alert;

FIGS. 6A-6F illustrate a series of steps for performing a procedure ofprobing a drilled hole and subsequently obtaining a depth measurementusing another embodiment of a medical device consistent with the presentdisclosure;

FIG. 7 is another embodiment of a medical device consistent with thepresent disclosure having a display for providing a digital readout of adepth measurement of the hole;

FIG. 8 is another embodiment of a medical device consistent with thepresent disclosure configured to wirelessly communicate with andtransmit depth measurement data to a wireless computing device torecord, store, and/or visually display measured depths;

FIGS. 9 and 10 illustrate the compatibility of a medical device of thepresent disclosure with other medical devices so as to provideadditional features, in additional bone probing and depth measurement,such as energy emission (FIG. 9) and sensing capabilities (FIG. 10);

FIG. 11 is a perspective view of a medical device consistent with thepresent disclosure and having a neuromonitoring port configured toreceive a corresponding input connector from a nerve sensing/nervestimulation device and provide an electrical pathway to the bone probe;

FIG. 12 is a side view, partly in section, of the medical device of FIG.11 illustrating the configuration of the bone probe shaft to carryelectrical signals to and from the nerve sensing/nerve stimulationdevice;

FIGS. 13A, 13B, and 13C illustrate the transmission of a signal frombone probe to a screw positioned within a hole in a vertebra forneuromonitoring capabilities; and

FIG. 14 illustrates an angle guide for use with the medical device ofthe present disclosure.

For a thorough understanding of the present disclosure, reference shouldbe made to the following detailed description, including the appendedclaims, in connection with the above-described drawings. Although thepresent disclosure is described in connection with exemplaryembodiments, the disclosure is not intended to be limited to thespecific forms set forth herein. It is understood that various omissionsand substitutions of equivalents are contemplated as circumstances maysuggest or render expedient.

DETAILED DESCRIPTION

By way of overview, the present disclosure is generally directed to amedical device for use in a bone implant fixation procedure andconfigured to provide a faster and more accurate measure of depth. Inparticular, the device includes a combination of a bone probe allowingfor physical examination of a hole drilled in a bone and a depth gaugemember for determining a depth of the hole and providing a digitalmeasurement of the depth. Accordingly, the device of the presentdisclosure is capable of digitally measuring the depth of an opening ina bone during the same surgical step that a surgeon probes and inspectsthe interior of the opening.

The device of the present disclosure includes a bone probe that allowsfor a surgeon to feel the interior side walls and base of the hole tolocate any cracks or other unintended openings or irregularities alongthe interior of the hole. The bone probe generally includes an elongatedshaft slidably mounted within a body of the device serving as a handleadapted for manual manipulation. The elongated shaft of the probeincludes a distal end configured to extend from the body of the deviceduring use. The distal end includes a probing tip for contacting aninterior portion of the hole. At least a portion of the elongated shaftmay be substantially flexible or semi-rigid to provide a proper “feel”to the surgeon during examination of the hole in the bone. For example,the shaft of the bone probe may be substantially non-elastic such thatthe surgeon can apply pressure against the interior wall of the hole tofeel for irregularities or the base of the hole via tactile feedbackprovided by the shaft. In some embodiments, the shaft may be taperedsuch that the shaft narrows in width in a direction towards the probingdistal tip. In this manner, the flexibility of the shaft may increasealong the shaft in a direction toward the probing tip.

The probing tip may include at least a first portion having a shape orcontour that aids the surgeon in detecting surface irregularities (e.g.,cracks, crevices, openings, etc.) on the interior surface of the hole.For example, in some embodiments the first portion may have asubstantially arcuate or curved shape. The arcuate or curved portion mayalso aid the surgeon in locating the bottom or base of the hole so as toallow for the depth of the hole to be measured via the depth gaugemember. The arcuate or curved shape of the first portion of the probingtip may generally lessen risk of tissue irritation that may otherwiseoccur along the interior surface of the hole, which is usually soft andeasily penetrable with less curved and more abrupt surfaces (with sharpor distinct edges). In some embodiments, the first portion may have agenerally spherically shape. In other embodiments, the first portion maybe substantially planar with rounded edges.

The probing tip may also include a second portion positioned oppositethe first portion, wherein the second portion includes an engagementsurface configured to pierce or otherwise establish purchase with aninterior of the hole upon application of sufficient force from thesurgeon. In particular, upon locating the base or bottom of the hole,the surgeon may then apply sufficient force upon the shaft of the boneprobe so that the engagement surface of the probing tip engages andestablishes purchase with a sidewall immediately adjacent the base ofthe hole. Upon establishing engagement, the medical device may bestabilized in position, at which point, the depth gauge member can beused for measuring the depth of the hole. In some embodiments, theengagement surface may include surface texturing to enhance frictionbetween the engagement surface and a portion of bone. For example, insome procedures in which a plate or implants is to be secured withscrews through a bicortical drill hole, the probing tip may extendentirely through the hole (from one side of the bone to the other), atwhich point the surgeon may pull the bone probe back towards the holesuch that the engagement surface of the second portion of the probingtip establishes purchase with one side of the bone, and the surfacetexturing enhances friction between the engagement surface and bone toreduce risk of slippage.

The depth gauge member generally includes a hollow elongated bodyslidably mounted within the body of the device and includes a distal endconfigured to extend from the first end of the body during use. Thehollow elongated body includes a lumen in which at least a portion ofthe bone probe shaft is received within such that the bone probe anddepth gauge member are independently slidable relative to one anotherand the body of the device.

The device further includes at least one sensor configured to generatean electronic signal indicative of a depth of the hole as a result ofsensing a distance between the first end of the device body and thedistal end of the depth gauge member. For example, in one embodiment,upon establishing purchase with a bottom interior surface of the holevia the probing tip, a surgeon need only move the device handle (i.e.,device body) in a direction towards the bone such that the first end ofthe handle contacts a surface of the bone proximate the open end of thehole or a surface of a plate or implant to be fixed to the bone. Thesurgeon may then advance the depth gauge member towards hole in thebone, such that the distal end of the depth gauge member extends fromthe first end of the device handle and advances into the hole, slidingover the bone probe. While the bone probe is maintained in engagementwith the bottom of the hole via the probing tip, the depth gauge membermay be advanced in a direction towards the bottom of the hole until thedistal end of the depth gauge member makes contact with the bottom ofthe hole. The bone probe essentially acts as a guide upon which thedepth gauge members slide over when advancing to the bottom of the hole.

The sensor is configured to generate an electronic signal based on adistance between the first end of the body and the distal end of thedepth gauge member, wherein the electronic signal is indicative of atleast a depth of the hole. In particular, the sensor may includeinductive or capacitive elements or assemblies configured to sense thelocation of the distal end of the depth gauge member relative to thefirst end of the device body, and, as a result, generate an electronicsignal representing the distance there between. Accordingly, the senseddistance between the first end of the device handle (when abutting thebone surface) and the distal end of the depth gauge member (whenabutting the bottom of the hole) is the depth of the hole.

Accordingly, the digital sensing of the hole depth provides a much moreaccurate measurement than conventional analog depth gauges and alsorequiring very little, if any, input or interpretation from the surgeon.Accordingly, by providing a much more accurate measurement of a holedepth, the surgeon is able to select the correct length screw for anygiven hole so as to improve the chances of a successful surgery.

FIG. 1 is top view of one embodiment of a medical device 100 consistentwith the present disclosure and FIG. 2 provides a cross-sectional viewof the medical device 100. As shown, the medical device 100 includes abody 102 having a first end 104 and an opposing second end 106 and isgenerally hollow. The body 102 is configured as a handle and generallyadapted for manual manipulation. Accordingly, the body will be referredto a “handle 102” hereinafter for ease of explanation.

The device 100 further includes a bone probe 108 slidably mounted withinthe handle 102. The bone probe 108 includes a shaft 110 having a distalend 112 configured to extend from, and retract towards, the first end104 of the handle 102 during use, as will be described in greater detailherein. The distal end 112 further includes a probing tip 114, which isuseful for examination and inspection of interior surfaces of a drilledhole in bone, as will be described in FIGS. 3A and 3B.

The device 100 further includes a depth gauge member 116 slidablymounted within the handle 102. The depth gauge member 116 generallyincludes a hollow elongated body 118 having a distal end 120 configuredto extend from, and retract towards, the first end of the handle 102during use, similar to the bone probe shaft 110, as will be describedherein. The hollow elongated body 118 has a lumen in which at least aportion of the bone probe shaft 110 is received such that the bone probe108 and depth gauge member 116 are independently slidable relative toone another and the handle 102. The device 100 further includes one ormore depth measurement sensors 122 configured to generate an electronicsignal indicative of a depth of at least the hole, wherein theelectronic signal varies in relation to a distance between the first end104 of the handle 102 and the distal end 120 of the depth gauge member116, as will be described in greater detail herein.

The bone probe 108 and depth gauge member 116 may each be coupled toseparate slider members for allowing a surgeon to manually controlmovement of the bone probe 108 and depth gauge member 116 independent ofone another. For example, as shown in FIG. 1, a first slider 124 may becoupled to at least the bone probe shaft 110 and is slidable along alongitudinal axis of the handle 102, which such movement of the firstslider 124 causes corresponding movement of the bone probe shaft 110.Although not shown in FIGS. 1 and 2, a second slider may be coupled tothe depth gauge member 116 and is similarly slidable along thelongitudinal axis of the handle 102, such that movement of the secondslider causes corresponding movement of the depth gauge member 116.

The device 100 may further include a spring assembly 126 coupled to atleast one of the bone probe 108 and depth gauge member 116. The springassembly 126 may be configured to provide a biasing force upon at leastone of the bone probe 108 and depth gauge member 116 so as to maintaineither the bone probe 108 or depth gauge member 116 in a defaultextended position. For example, as shown in FIGS. 1 and 2, the boneprobe 108 is generally positioned in an extended configuration (probingtip 114 extended out of first end 104 of handle 102), in which a surgeonmay now examine an interior surface of a drilled hole, as is shown inFIGS. 4A and 4B.

During a bone-related procedure involving placement of a screw, or otherfastener, it may be desirable to determine whether drilling of the holeresulted in any cracks or openings, either along an interior side wallof the hole or at the base of the hole. Ensuring the integrity of thedrilled hole is important because unintended cracks, openings, orirregularities can increase the risk that the screw will either notsecurely attach itself within the hole or may result in chipping orfragmenting of bone during fastening of the screw within the hole. It isgenerally not possible for a surgeon to visual examine the integrity ofthe drilled hole due to a limited field of view within the hole (drilledholes can be relatively small in width, such as 5 mm or less in someinstances).

The bone probe 108 allows for a surgeon to feel the interior side wallsand bottom of a drilled hole so as to locate any cracks or otherunintended openings or irregularities along the interior of the hole.For example, probing tip 114 is configured for contacting an interiorportion of the hole and at least a portion of the elongated shaft 110may be substantially flexible or semi-rigid to provide a proper “feel”to the surgeon during examination of the hole in the bone. For example,the shaft 110 of the bone probe 108 may be substantially non-elasticsuch that the surgeon can apply pressure against the interior wall ofthe hole to feel for irregularities or the base of the hole via tactilefeedback provided by the shaft 110. In some embodiments, the shaft 110may be tapered such that the shaft narrows in width in a directiontowards the probing distal tip. In this manner, the flexibility of theshaft may increase along the shaft in a direction toward the probing tip114.

FIGS. 3A and 3B are enlarged front and side views, respectively, of oneembodiment of a probing tip 114 a defined on the distal end 112 of thebone probe shaft 110. As shown, the probing tip 114 a may include anarcuate first portion 128 shaped and configured to contact an interiorsurface of the hole with little or no resistance and provide tactilefeedback of the interior surface to the surgeon. For example, as shown,the first portion 128 is substantially curved or spherical so as toprevent or minimize the risk that the probing tip 114 a would penetrateor otherwise engage of portion of the interior surface of the hole.Rather, the first portion 128 is shaped so as to glide or easily slidealong the interior surface, while still allowing sufficient contact toprovide tactile feedback to the surgeon. Accordingly, the arcuate firstportion 128 may lessen or eliminate tissue irritation that may otherwiseoccur when a sharper object is used to probe the bone opening.

The probing tip 114 a further includes a second portion 130 having anengagement surface shaped and configured to establish purchase with aportion of the interior surface of the hole and associated with a bottomof the hole upon sufficient application of force to the shaft. Theengagement surface may be a substantially abrupt edge of the probing tip114, in which the transition between the first portion 128 and secondportion 130 is sudden (e.g., sharp corner or edge). Accordingly, uponsufficient pressure, the engagement surface is configured to pierce orestablish purchase with tissue in the interior of the hole. Thus, theprobing tip 114 a is multifunctional in that the first portion 128allows for probing of the interior surfaces to provide a surgeon with a“feel” for examination purposes and to further locate the bottom of thehole and the second portion 130 allows for the surgeon to establishpurchase at the desired site (i.e., the bottom of the hole) so as tostabilize the bone probe in the desired position, at which point, thedepth gauge member can be used for measuring the depth of the hole.

In some embodiments, the engagement surface of the second portion 130may include surface texturing to enhance friction between the engagementsurface and a portion of bone. For example, in some procedures in whicha plate or implants is to be secured with screws through a bicorticaldrill hole, the probing tip may extend entirely through the hole (fromone side of the bone to the other), at which point the surgeon may pullthe bone probe back towards the hole such that the engagement surface ofthe second portion of the probing tip establishes purchase with one sideof the bone, and the surface texturing enhances friction between theengagement surface and bone to reduce risk of slippage.

FIGS. 3C and 3D are enlarged front and side views, respectively, ofanother embodiment of a probing tip 114 b defined on the distal end 112of the bone probe shaft 110. As shown, the probing tip 114 b may includea first portion 129 shaped and configured to contact an interior surfaceof the hole with little or no resistance and provide tactile feedback ofthe interior surface to the surgeon. For example, as shown, the firstportion 129 has a substantially planar or flat surface with roundededges so as to prevent or minimize the risk that the probing tip 114 bwould penetrate or otherwise engage of portion of the interior surfaceof the hole. Rather, the rounded edges of the first portion 129 areshaped so as to glide or easily slide along the interior surface, whilestill allowing sufficient contact to provide tactile feedback to thesurgeon. The substantially planar surface may yield a more accuratedepth measurement than a full radius bottom in that, in somecircumstances, the flat surface may provide better engagement and sitmore flush with the bottom of the hole than the full radius firstportion 128 of probing tip 114 a (in FIGS. 3A and 3B). It should benoted, however, that the round edges may still provide enough edge toserve as an engagement surface for establishing purchase with a portionof the interior surface of the hole and associated with a bottom of thehole upon sufficient application of force to the shaft. The secondportion 131 of probing tip 114 b may be substantially curved orspherical.

FIGS. 4A and 4B illustrate an initial process of examining, via the boneprobe 108, a drilled hole 134 in a bone 132. For example, as previouslydescribed herein, the biasing force from the spring assembly 126 may besufficient so as to maintain the bone probe 108 in the extended positionwhile the surgeon probes an interior surface 136 of the drilled hole 134and locates the bottom 138 of the hole 134. However, as shown in FIG.4B, the biasing force may be overcome upon a surgeon moving the handle102 in a direction towards the hole 134 once the desired target site islocated, such as locating the bottom 138 of the hole 134. The surgeoncan move the handle 102 until the first end 104 of the handle 102 abutseither the surface of the bone 132 or a surface of a plate or implant140, as indicated by arrow 142, thereby resulting in compression of thespring assembly 126 while maintaining placement of the probing tip 114at the bottom 138 of the hole 134, as indicated by arrow 144. At thispoint, the depth gauge member 116 can be advanced in a direction towardsthe hole 134, such that the hollow shaft 118 slides over the bone probeshaft 110, wherein the bone probe shaft 110 generally acts as a guideand holding position as a result of the engagement surface of the secondportion 130 of the probing tip 114 having established purchase with thebottom 138 of the hole 134. The depth gauge member 116 can be extendeddown into the hole 134 until the distal end 120 of the depth gaugemember 116 abuts the bottom 138 of the hole 134. Accordingly, the one ormore depth measurement sensors 122 can then generate an electronicsignal in relation to a distance between the first end 104 of the handle102 and the distal end 120 of the depth gauge member 116, wherein theelectronic signal is indicative of the depth of the hole 134 and thethickness of the plate or implant 140.

The device 100 of the present disclosure may include a variety ofdifferent sensing devices suitable for determining a length or depth ofthe drilled hole or bore to be measured. For example, the one or moredepth measurement sensors 122 may include, but are not limited to, anelectromechanical or electronic sensor, such as a linear encoder, andmay employ any one or more of acoustic, ultrasound, capacitive, electricfield, inductive, electromagnetic (e.g., Hall effect-type) and opticalcomponents for determining relative or absolute distance measurements.In some embodiments, the sensors 122 may be configured to measure,sense, discriminate, or otherwise determine a length or distance betweenat least the first end 104 of the handle 102 and the distal end 120 ofthe depth gauge member 116.

For example, in one embodiment, as shown in FIGS. 4A and 4B, at least afirst sensor element 122 a is positioned proximate to the first end 104of the handle 102 and a second sensor element 122 b is positioned on thedepth gauge shaft 118 proximate the distal end 120. The sensor elements122 a, 122 b are configured to measure at least one of relative,absolute and incremental movement (e.g., distance, speed, etc.) of thedepth gauge shaft 118 with respect to the first end 104 of the handle102 during a measurement procedure. For example, in one embodiment, thesensor elements 122 a, 122 b may be used for measure an absolutedistance that the depth gauge 116 distal end 120 is moved relative tothe fixed reference point such as, for example the first end 104 of thehandle 102.

The first sensor element 122 a may be an active inductive, capacitive oroptical element that is in communication with circuitry (e.g., acontroller) of a user interface portion of the device (e.g., a GUIdisplay or the like with user inputs). The first sensor element 122 amay include one or more longitudinally-extending conductors that arewires, cables or traces on a printed circuit board such as, for example,a flex-circuit or the like. Furthermore, the first sensor element 122 amay further include a plurality of inductive, capacitive or opticalelements that may be coupled with and disposed on thelongitudinally-extending conductors. The second sensor element 122 b maybe configured on the depth gauge shaft 118 in manner so as to cooperatewith the first sensor element 122 a proximate the first end 104 of thehandle 102. For example, the second sensor element 122 b may be agenerally passive element such as a permanent magnet, optical element(e.g., indicia) or the like that is configured to cooperate, communicateor otherwise interact with the first sensor element 122 a. For example,during a measurement procedure, movement of the depth gauge 116 out ofthe device handle 102 results in interaction between the first andsecond sensor elements 122 a, 122 b. In particular, as the depth gauge116 extends from the device handle 102, the first and second sensorelements 122 a, 122 b move relative to one another (i.e., second sensorelement 122 b moves past first sensor element 122 a and, in combinationwith one another, provide signals (e.g., pulses, etc.) to the circuitry,which processes the signals and displays a distance measurement on adisplay and/or transmits the signals to separate computing devices.

In various embodiments of the present invention, the one or more sensors122 may be connected with a microprocessor and/or other digitalelectronic device in order to produce an output for an electronicdisplay, such as a liquid crystal display or light-emitting diodedisplay, and or for wireless/wired transmission of electronic signals,comprising the measurement data, to a wireless compatible computingdevice. For example, in some embodiments, the microprocessor or otherdigital electronic device may be connected to a wireless transmitter forwireless transmission of electronic signals. In some embodiments, asignal conditioning circuit may interpose the inductive or capacitiveelements of the electronic sensor and the microprocessor or otherdigital electronic device used to drive the display, thus ensuring thatcorrect input current and voltage levels are provided to the variouscomponents. The device may further include a power source, such as aprimary or secondary battery, may be connected to the signalconditioning circuit or to the microprocessor directly.

It should be noted that the device 100 of the present disclosure mayinclude a variety of different electronic sensor and circuitryassemblies for determining and transmitting depth measurements,including the sensors and systems discussed in U.S. Pat. Nos. 7,165,336;7,444,756; 7,493,703; 7,607,238; 7,676,943; 7,685,735; 7,730,629;7,895,762; 7,895,767, the contents of each of which are herebyincorporated by reference in their entirety.

FIG. 5 is a side view of the medical device 100 including a strainsensor 146 for sensing strain upon the bone probe shaft 110 as a resultof probing the interior surface of a drilled hole. The sensor 146 mayinclude a strain gauge or the like configured to determine a strain ofthe bone probe shaft 110, which may be useful for alerting the surgeonof an amount of resistance that the distal probing tip 114 isencountering during probing of the interior of the hole. For example,while a surgeon may be able to “feel” the interior surface and furtherhave a sense of when the probing tip 114 actually makes contact with thebottom of the hole, the strain sensor 146 may further generate anelectronic signal based on a sensed strain of the shaft 110 which maythen be used to provide an audible and/or visual alert, via a device 148(i.e., speaker or lights) to the surgeon indicating that the probing tip116 is in fact positioned at the bottom of the hole.

For example, the resistance encountered when the probing tip 116 engagesthe bottom of the hole may have a certain strain value (i.e., above acertain threshold) which may be different than a resistance encounteredwith the sidewalls of the hole (which may have a softer, spongiertissue). Accordingly, the audible and/or visual alert may confirm to asurgeon whether they are in fact positioned at the bottom of the hole orif too much pressure is being placed against the interior surface suchthat they risk possibly inadvertently piercing the interior surface.

FIGS. 6A-6F illustrate a series of steps for performing a procedure ofprobing a drilled hole and subsequently obtaining a depth measurementusing another embodiment of a medical device 200 consistent with thepresent disclosure. As shown, the device 200 may be similarly configuredas device 100 previously described herein. However, as shown in FIG. 6A,both the bone probe 108 and depth gauge member 116 may both becompletely withdrawn into the handle 102 until either a first slider 224is moved, resulting in corresponding movement of the bone probe 108, ora second slider 250 is moved, resulting in corresponding movement of thedepth gauge member 116, as shown in FIG. 6E.

In addition to including sliders for allowing independent movement ofthe bone probe and depth gauge member, the device 200 further includes alocking member 252 for locking a position of at least the bone probe108. As shown, the locking member 252 is coupled to the first end 104 ofthe handle 102 and is associated with at least the bone probe 108 insuch as manner so as to allow/prevent movement of the bone probe 108.For example, the locking member 252 has an unlocked configuration and alocked configuration, wherein, in the unlocked configuration, thelocking member 252 allows the bone probe 108 to freely move and, when inthe locked configuration, the locking member 252 prevents movement ofthe bone probe 108.

For example, upon extending the bone probe 108, a surgeon may then placethe locking member 252 in a locked configuration, as shown in FIG. 6C,in which the locking member 252 is configured to provide sufficientcontact with the bone probe shaft 110 so as to prevent, or makedifficult, the movement of the bone probe shaft 110 relative to thefirst end 104 of the handle 102, thereby providing an amount of rigidityto the probe shaft 110. Accordingly, a surgeon may now performexamination of a drilled hole without concern of the bone probe 108withdrawing back into the handle 102 or being loose.

Upon locating the base or bottom of the hole, the surgeon may then applysufficient force upon the bone probe shaft 110 so that the engagementsurface of the second portion of the probing tip engages and establishespurchase with the bottom of the hole, or a sidewall immediately adjacentto the bottom, as shown in FIG. 6D. Upon establishing engagement, thesurgeon may then place the locking member 252 in an unlockedconfiguration, now that the bone probe shaft 110 is in a stabilized inposition. The surgeon may then move the handle in a directions towardsthe bone until the first end of the handle abuts the surface of the boneor the surface of the plate/implant, as shown in FIG. 6E, at whichpoint, the depth gauge member 116 can be used for measuring the depth ofthe hole. As shown in FIG. 6F, the surgeon may then advance the depthgauge member 116 towards hole, via the second slider 250, such that thedistal end 120 of the depth gauge member shaft 118 extends from thefirst end of the device handle and advances into the hole, sliding overthe bone probe 108. While the bone probe 108 is maintained in engagementwith the bottom of the hole via the probing tip, the depth gauge membermay be advanced in a direction towards the bottom of the hole until thedistal end of the depth gauge member makes contact with the bottom ofthe hole. The bone probe essentially acts as a guide upon which thedepth gauge member slide over when advancing to the bottom of the hole.

The sensor is configured to generate an electronic signal based on adistance between the first end of the body and the distal end of thedepth gauge member, wherein the electronic signal is indicative of atleast a depth of the hole. In particular, the sensor may includeinductive or capacitive elements or assemblies configured to sense thelocation of the distal end of the depth gauge member relative to thefirst end of the device body, and, as a result, generate an electronicsignal representing the distance there between. Accordingly, the senseddistance between the first end of the device handle (when abutting thebone surface) and the distal end of the depth gauge member (whenabutting the bottom of the hole) is the depth of the hole.

It should be noted that the device may include logic or allow foradjustment to the sensing capabilities so as to program the sensor toaccount for other variables when sensing the depth of the hole. Forexample, in some embodiments, certain procedures require fixing a plateor implant to the bone via screws. Accordingly, the screw length mustnot only be sufficient to fill the hole but also long enough to accountfor the thickness of a plate or implant through which it passes whenengaging the hole. Accordingly, in some embodiments, the sensor may beprogrammed so as to account for the thickness of the plate or implantand will further include that thickness in the electronic signalproduced, such that the electronic signal is indicative of the totaldepth that a corresponding screw length will need to cover, includingthe depth of the hole in the bone in addition to the thickness of theplate or implant through which the screw will pass through and the screwhead will engage.

Furthermore, in some instances, first end of the device handle will bedirectly abutting a surface of the plate or implant, as shown in FIG.6F, which is directly abutting the surface of the bone, when the surgeonis measuring the depth. Thus, in this case, the sensor is still able tosense a distance between the first end of the device handle and thedistal end of the depth gauge member, which will provide an overalldepth, rather than just a depth of the hole in the bone.

FIG. 7 is another embodiment of a medical device 300 consistent with thepresent disclosure having a display 354 for providing a digital readoutof a depth measurement of the hole based on the electronic signal fromthe sensor. The display 354 may include a liquid crystal display or anLED display, for example.

FIG. 8 is another embodiment of a medical device 400 consistent with thepresent disclosure configured to wirelessly communicate with andtransmit depth measurement data to a wireless computing device 500 overa network, to record, store, and/or visually display measured depthsbased on electronic signals from the sensor for determining depth ofdrilled holes. For example, the device 400 may include a wirelesstransmitter 456 configured to wireless communicate and exchangeinformation, including the electronic signal, with a wireless display orcomputing device 500 for at least visually providing a depth measurementof the hole based on the electronic signal from the sensor. The separatedisplay or computing device 500 may include, but is not limited to, amonitor or panel display, a PC, a notebook, a tablet computer, asmartphone, or other computing device configured to wirelesslycommunicate with the wireless transmitter 456.

The network may be any network that carries data. Non-limiting examplesof suitable networks that may be used as network include WiFi wirelessdata communication technology, the internet, private networks, virtualprivate networks (VPN), public switch telephone networks (PSTN),integrated services digital networks (ISDN), digital subscriber linknetworks (DSL), various second generation (2G), third generation (3G),fourth generation (4G) cellular-based data communication technologies,Bluetooth radio, Near Field Communication (NFC), the most recentlypublished versions of IEEE 802.11 transmission protocol standards, othernetworks capable of carrying data, and combinations thereof.

Furthermore, in some embodiments, the computing device 500 may include aspecific software application that may be directed to maintaining arecord of the hole measurements and/or provide an interactive userinterface (GUI) in which multiple holes can be mapped to a particularplate or implant and the depth of each hole (including the thickness ofthe plate or implant) can be included and stored for records.

FIGS. 9 and 10 illustrate the compatibility of a medical device of thepresent disclosure with other medical devices so as to provideadditional features, in additional bone probing and depth measurement,such as energy emission (FIG. 9) and sensing capabilities (FIG. 10). Forexample, in some embodiments, the bone probe shaft 110 may include anelectrically conductive material (e.g., a metal such as stainless steel,nitinol, or aluminum), wherein a portion of the bone probe shaft 110 maybe exposed, or otherwise accessible, along a portion of the devicehandle. In particular, the device handle may include an access region158 that may be in the form of an aperture, window, or the like, thatprovides access to an interior of the handle, particularly providingaccess to an exposed portion of the bone probe shaft. Thus, in someembodiments, an electrical current from a separate device 600, 700 maybe supplied to the bone probe shaft via the access region 158 (e.g.,slide a working tip of an electrocautery device 600 into the accessregion 158 to make contact with bone probe shaft 110). Accordingly, as aresult of being made from a conductive material, the bone probe shaft110 may carry the electrical current to the distal probe tip, which maythen be used to deliver energy to a desired target (e.g., interiorsurface of hole of the bone) as a result of the electrical currentapplied thereto. Similarly, a separate nerve sensing/stimulation device700 (shown in FIG. 10) may be coupled to the conductive bone probe shaftvia the access region, such that the distal probe tip essentially actsas an extension to the nerve sensing/stimulation device and may be usedto sense/stimulate nerves within the bone. The separate sensing/nervestimulation device or system 700 may include, for example, existingcapital equipment or a handheld battery-powered neuromonitoring device.

FIG. 11 is a perspective view of a medical device 100 having a port 160provided on the proximal, or second end 106, of the device body 102. Theport 160 is configured to receive a corresponding input connector from anerve sensing/nerve stimulation device 700. The port 160 (hereinafterreferred to as “neuromonitoring port 160”) is coupled to the bone probeshaft 108 and is configured to provide an electrical pathway from thenerve sensing/nerve stimulation device 700 to the bone probe 108 uponinsertion of the input connector into the neuromonitoring port 160. Aspreviously described, the bone probe shaft 110 may include anelectrically conductive material (e.g., a metal such as stainless steel,nitinol, or aluminum) and thus may carry an electrical signal. Thus, insome embodiments, an electrical signal from the nerve sensing/nervestimulation device 700 may be supplied to the bone probe shaft 110 viathe neuromonitoring port 160. Accordingly, as a result of being madefrom a conductive material, the bone probe shaft 110 may carry theelectrical signal to the distal probe tip 114, which may then be used tosense/stimulate nerves adjacent or in close proximity to the drilledhole in the bone, either when the bone probe 108 is directly placedwithin the drilled hole or when the bone probe 108 is in contact with ascrew placed within the drilled hole.

FIG. 12 is a side view, partly in section, of the medical device 100 ofFIG. 11 illustrating the configuration of the bone probe shaft 110 forcarrying electrical signals to and from the nerve sensing/nervestimulation device. Upon insertion of the electrical connector into theneuromonitoring port 160, a pathway is provided between the nervesensing/nerve stimulation device 700 and the bone probe 108. The boneprobe shaft 108 generally includes a soft coil portion 162 configured toallow conduction of an electrical signal provided by the nervesensing/stimulation device 700 while the shaft 110 moves between fullyretracted and fully extended positions and intermediate positions therebetween, particularly when measuring the depth of the drilled hole 134.In some embodiments, a portion of the distal end 112 of the bone probe108, particularly the exposed portion of the shaft 110 extendableoutside of device body 102 may include an insulating material 164, whilethe distal probing tip 114 is free of insulating material.

FIGS. 13A, 13B, and 13C illustrate the transmission of a signal frombone probe 108 to a screw positioned within a hole in a vertebra forneuromonitoring capabilities, particularly useful during an open spinalprocedure. As shown in FIG. 13A, upon coupling the nerve sensing/nervestimulation device 700 to the medical device 100 (e.g., inserting theelectrical connector into the neuromonitoring port 160), a surgeon canbegin a neuromonitoring procedure to determine whether there are anycritical neurological structures adjacent to or within an unsafeproximity to the drilled hole and screw. In particular, a surgeon canperform neuromonitoring procedure by placing the bone probe 108 directlywithin the drilled hole prior to screw placement, in which the distalprobing tip 114 can be placed in direct contact with the interior of thehole and transmit the electrical signal from the nerve sensing/nervestimulation device 700 to the bone tissue and will subsequently receivea response signal to then be carried back to the nerve sensing/nervestimulation device 700 for processing. In another method, as shown inFIGS. 13A, 13B, and 13C, the surgeon is performing the neuromonitoringprocedure once the screw is already in place (e.g., already fittedwithin the drilled hole) by placing the distal probing tip 114 in directcontact with the screw, which, in turn, will act as a conduit and carryelectrical signals to and from the distal probing tip 114 and the nervesensing/nerve stimulation device 700.

Accordingly, the medical device consistent with the present disclosureis a three-in-one single use device designed to more accurately andsafely measure the screw hole pathway. For example, the probing tip ofthe bone probe provides a user (e.g., surgeon) with superior tactilefeedback to assist the surgeon in confirming a safe pathway within thebone. The electronic measurement/digital sensing is designed to providemore accurate depth measurement for the screw pathway. Theneuromonitoring feature is used to stimulate the pathway and/or screw,ensuring the screw is safely positioned away from any criticalneurological structures. Overall, the medical device of the presentdisclosure is a faster, safer, more accurate and user-friendly solutionfor surgeons when placing bone screws, particularly pedicle screwsduring spinal fusion surgery, thereby minimizing spine surgerycomplications and reducing overall healthcare costs.

FIG. 14 illustrates an angle guide 800 for use with the medical deviceof the present disclosure. In some instances, holes may be drilled intobone at an angle. Accordingly, the angle guide may be useful inproviding a surgeon with a visual guide as to the correct angle at whichto position the device when attempting to examine the hole and furtherlocate the bottom of the hole to carry out the depth measurements.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, appearances of the phrases “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.Furthermore, the particular features, structures, or characteristics maybe combined in any suitable manner in one or more embodiments.

The terms and expressions which have been employed herein are used asterms of description and not of limitation, and there is no intention,in the use of such terms and expressions, of excluding any equivalentsof the features shown and described (or portions thereof), and it isrecognized that various modifications are possible within the scope ofthe claims. Accordingly, the claims are intended to cover all suchequivalents.

What is claimed is:
 1. A device for examination and measurement of a bore hole formed in a bone, the device comprising: a handle including a first end and a second end; a bone probe slidably mounted within the handle, the bone probe comprising a shaft including a distal end defining a probing tip comprising: a first portion shaped and configured to contact an interior surface of the bore hole with little or no resistance and provide tactile feedback of the interior surface of the bore hole to a user; and a second portion including an engagement surface shaped and configured to establish purchase with a portion of the interior surface of the bore hole and associated with a bottom of the bore hole upon sufficient application of force to the shaft; a depth gauge member slidably mounted within the handle, the depth gauge member comprising a hollow elongate body including a distal end, the hollow elongated body including a lumen in which at least a portion of the bone probe shaft is received such that the bone probe and depth gauge member are independently slidable relative to one another and the handle; and a sensor configured to generate an electronic signal indicative of a depth of the bore hole, wherein the electronic signal varies in relation to a distance between the first end of the handle and the distal end of the elongate body of the depth gauge member.
 2. The device of claim 1, wherein the first portion of the probing tip comprises a substantially arcuate shape.
 3. The device of claim 1, wherein the first portion of the probing tip comprises a substantially planar surface.
 4. The device of claim 1, wherein the engagement surface of the second portion of the probing tip has surface texturing to enhance friction between the engagement surface and a portion of bone.
 5. The device of claim 1, wherein the sensor is an electrical resistance-based sensor.
 6. The device of claim 1, further comprising a display on the handle configured to visually provide a digital readout of a depth measurement of the hole based on the electronic signal from the sensor.
 7. The device of claim 6, wherein the display is a liquid crystal display or an LED display.
 8. The device of claim 1, further comprising a first slider coupled to the bone probe shaft and slidable along a longitudinal axis of the handle, wherein movement of the first slider causes corresponding movement of the bone probe shaft.
 9. The device of claim 8, further comprising a second slider coupled to the depth gauge member and slidable along the longitudinal axis of the handle, wherein movement of the second slider causes corresponding movement of the depth gauge member.
 10. The device of claim 1, further comprising a locking member coupled to the first end of the handle and associated with at least the bone probe, the locking member having an unlocked configuration and a locked configuration.
 11. The device of claim 10, wherein, when in the unlocked configuration, the locking member allows the bone probe shaft to move relative to the first end of the handle.
 12. The device of claim 10, wherein, when in the locked configuration, the locking member provides sufficient contact with the bone probe shaft to prevent, or make difficult, movement of the bone probe shaft relative to the first end of the handle.
 13. The device of claim 1, further comprising a sensor configured to generate an electronic signal indicative of strain of the bone probe shaft.
 14. The device of claim 13, further comprising an alert device for receiving the electronic signal indicative of strain from the sensor and output at least one of an audible alert or a visual alert providing an indication to a user of the degree of strain upon the bone probe shaft.
 15. The device of claim 1, further comprising a wireless transmitter/receiver configured to wirelessly communicate and exchange information, including the electronic signal, with a wireless display or computing device for at least visually providing a depth measurement of the bore hole based on the electronic signal from the sensor.
 16. The device of claim 1, wherein the handle comprises a port in communication with a portion of the bone probe shaft and provides access from an exterior of the handle to an interior of the handle and to the bone probe shaft.
 17. The device of claim 16, wherein the bone probe shaft comprises an electrically conductive material.
 18. The device of claim 17, wherein the port is configured to receive and place an input connector of a second medical device into electrical communication with the bone probe shaft, wherein the bone probe shaft is configured to carry electrical signals to and from the input connector of the second medical device.
 19. The device of claim 18, wherein the second medical device comprises a neuromonitoring device.
 20. The device of claim 19, wherein the probing tip of the distal end of the bone probe shaft is configured to provide signals to the neuromonitoring device indicative of whether a nerve is present within or adjacent to the bore hole. 